Processing transdermal alcohol concentration (TAC) data to detect low-level drinking.

Area of Science:

• Forensic Science
• Alcohol Research
• Biomedical Engineering

Background:

• Alcohol monitoring systems (AMS), such as the SCRAM CAM device, use transdermal alcohol concentration (TAC) to objectively quantify drinking.
• Current AMS criteria are conservative, reliably detecting only heavy drinking (≥5 standard drinks).
• This study introduces novel Research Rules to process TAC data for detecting lower-level alcohol consumption.

Purpose of the Study:

• To develop and validate Research Rules for processing transdermal alcohol concentration (TAC) data.
• To enhance the detection sensitivity of alcohol monitoring systems (AMS) for low-level and moderate drinking.
• To compare the performance of Research Rules against standard AMS criteria in identifying alcohol consumption.

Main Methods:

• Sixteen males and 14 females wore TAC monitors for 28 days in natural environments.
• Participants self-reported daily alcohol consumption via text message prompts.
• Developed Research Rules were applied to TAC data to analyze detection of self-reported drinking events.

Main Results:

• Out of 606 positive TAC events, 345 were identified as potential drinking events by Research Rules, compared to 163 by AMS criteria.
• Research Rules detected 31% of lower-level drinking events missed by AMS, while maintaining 91% specificity.
• AMS criteria showed high specificity (99.8%) for heavy drinking but poor sensitivity for lower-level consumption and abstinence indication.

Conclusions:

• Standard AMS criteria provide high specificity for heavy drinking but are inadequate for monitoring abstinence or lower-level consumption.
• The developed Research Rules significantly improve the sensitivity of TAC data analysis for detecting any level of alcohol consumption.
• Research Rules offer a more comprehensive approach to quantifying alcohol intake, including low-to-moderate levels, while maintaining good specificity.